Windows 7 Green screen videos

I've noticed almost everytime I want to watch an embedded video on a website, or like just now on Erica's post about the comedy show on the Dec 10th, The video begins fine, than at about 30 seconds it either spazzes betweenn the video and a green screen or like Erica's it was fine up to the Tally Ho theater, and then it was just green. Of course, you can always still here the sound!